On the iPhone, there is a trick that allows you to get a bigger keyboard. Before the keyboard is shown, rotate the phone to the horizontal (wide-screen) position. Then tap to get the keyboard. The keyboard will be shown in the horizontal position, and it will be much bigger as a result.

While this is an awesome trick for thos of us with thick fingers, there there are some limitations. This *only* works with Safari and you need to perform the rotation *before* the keyboard is shown. Once the keyboard is shown, you won't be able to rotate the screen on the iPhone. Hopefully Apple will fix some of these shortcoming in the software with a future release. I know that I'd like to be able to get the horizontal keyboard in all the applications (it really is much nicer this way), and I'd like to be able to rotate while the keyboard is being shown.